in reply to Re^2: Most Significant Set Bit
in thread Most Significant Set Bit

Strangely using a stored $log2 = log(2) in the above test did not improve the log function speed. It was actually slightly slower.

EDIT: similar also with use constant log2 => log(2)

EDIT2: The interpreter must compile such constant expressions into a constant before running.

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Re^4: Most Significant Set Bit
by ikegami (Patriarch) on Mar 18, 2024 at 15:05 UTC

    The interpreter must compile such constant expressions into a constant before running.

    Yes 

    $ perl -MO=Concise,-exec -e'my $x = log(2);'
1  <0> enter v
2  <;> nextstate(main 1 -e:1) v:{
3  <$> const[NV 0.693147180559945] s/FOLD
4  <1> padsv_store[$x:1,2] vKS/LVINTRO
5  <@> leave[1 ref] vKP/REFC
-e syntax OK

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